[clang] [clang-tools-extra] [llvm] [clang] Introduce diagnostics suppression mappings (PR #112517)

[Boaz Brickner via cfe-commits]

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@@ -70,6 +76,16 @@ void clang::ProcessWarningOptions(DiagnosticsEngine &Diags,
   else
     Diags.setExtensionHandlingBehavior(diag::Severity::Ignored);
 
+  if (!Opts.DiagnosticSuppressionMappingsFile.empty()) {
+    if (auto Buf =
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bricknerb wrote:

[Buf](https://github.com/search?type=code&auto_enroll=true&q=repo%3Allvm%2Fllvm-project+%2Fbuf%5B%5Ef%5D.*%3D.*%5Cn%3F.*getBufferForFile%2F) is less common, and more so if we focus on Clang code. IIUC, this is the content of the file, FileBuffer or FileContent is more descriptive, and Buffer is better than Buf.

https://github.com/llvm/llvm-project/pull/112517